I recently received a HP Elitebook 820 G3, aside from the current Skylake power consumption issues, which I do not care so much about, I noticed the OK, but not as good as on Windows, Track Point.

On Windows it is detected as an Synaptics Trackpoint/Touchpad combo, on Linux however it is detected as 2 different devices.

$xinput list
⎡ Virtual core pointer                    	id=2	[master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer              	id=4	[slave  pointer  (2)]
⎜   ↳ PS/2 Generic Mouse                      	id=11	[slave  pointer  (2)]
⎜   ↳ SynPS/2 Synaptics TouchPad              	id=12	[slave  pointer  (2)]

The trackpoint:
$cat /sys/devices/platform/i8042/serio2/input/input9/uevent
PRODUCT=11/2/1/0
NAME="PS/2 Generic Mouse"
PHYS="isa0060/serio2/input0"
PROP=1
EV=7
KEY=70000 0 0 0 0
REL=3
MODALIAS=input:b0011v0002p0001e0000-e0,1,2,k110,111,112,r0,1,amlsfw

$cat /sys/devices/platform/i8042/serio2/uevent
DRIVER=psmouse
SERIO_TYPE=01
SERIO_PROTO=00
SERIO_ID=00
SERIO_EXTRA=00
MODALIAS=serio:ty01pr00id00ex00
SERIO_FIRMWARE_ID=PNP: SYN3039 SYN0100 SYN0002 PNP0f13


The touchpad:
$cat /sys/devices/platform/i8042/serio3/input/input11
PRODUCT=11/2/7/1b1
NAME="SynPS/2 Synaptics TouchPad"
PHYS="isa0060/serio3/input0"
PROP=1
EV=b
KEY=e520 30000 0 0 0 0
ABS=660800011000003
MODALIAS=input:b0011v0002p0007e01B1-e0,1,3,k110,111,145,148,14A,14D,14E,14F,ra0,1,18,1C,2F,35,36,39,3A,mlsfw

$cat /sys/devices/platform/i8042/serio3/uevent
DRIVER=psmouse
SERIO_TYPE=01
SERIO_PROTO=00
SERIO_ID=00
SERIO_EXTRA=00
MODALIAS=serio:ty01pr00id00ex00
SERIO_FIRMWARE_ID=PNP: SYN3039 SYN0100 SYN0002 PNP0f13

The main issues are, that two-button scrolling does not work and the speed of the trackpoint is to low, even with maxed out speed in gnome settings it is still pretty slow and mostly unusable.

I privately own the device and can provide additional information as needed.